This topic provides answers to some frequently asked questions (FAQ) about log loss, log deletion, and log cost reduction.
What do I do if specific logs cannot be found?
The related project or Logstore is deleted
If you delete a Logstore or project, the logs that are stored in the Logstore or project are deleted and cannot be restored. You can query the DeleteProject and DeleteLogStore events in the ActionTrail console. For information about how to query events, see Query events in the ActionTrail console.
The retention period of the logs ends
After the specified retention period ends, the corresponding logs are automatically deleted and cannot be restored. Simple Log Service deletes all expired data within 1 hour. The statistics that are displayed in Usage Details on the homepage of the Simple Log Service console is updated on the next day. For example, if you change the data retention period from 5 days to 1 day, Simple Log Service deletes the logs of the previous four days within 1 hour. For information about how to change the data retention period of a Logstore, see How do I delete logs?
No logs are collected
Click the Consumption Preview icon of a Logstore to check whether data is written to the Logstore.
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Click Diagnose to check whether a collection error occurs. For more information, see How do I troubleshoot the common errors that may occur when Simple Log Service collects logs?
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If no exceptions are displayed in the Consumption Preview and Log Collection Error panels, troubleshoot the issue based on the type of your logs. For server logs, see How do I troubleshoot an error that is related to a Logtail machine group in a host environment? For container logs, preview container metadata to check whether filter conditions are specified and whether the container metadata can match containers. Then, you can troubleshoot the issue based on the instructions that are described in What do I do if an error occurs when I use Logtail to collect logs from containers?
Overdue payments occur in Simple Log Service
If an overdue payment remains unsettled seven days after Simple Log Service is stopped, Alibaba Cloud assumes that you have stopped using Simple Log Service. In this case, your projects are released and data is deleted. Deleted data cannot be restored. For more information, see Overdue payments.
How do I delete a specific log from a Logstore? How do I reduce log storage costs?